Yeah, the title says it all. I technically lost my world because I somehow accidentally put it in creative mode and was never able to put it back. I'm honestly a bit pissed of by this, seeing how I've never come across a creative mode mod that doesn't allow you to switch from the creative mode.
I hope that there is a solution to this. If not, then I'll just start a new world and cheat my way to where I was command wise. Whatever.

EDIT: Almost forgot. Since I permanently have infinite items and all, whenever I re-enable creative mode with the infinite items selected, it just crashes my game and I'm forced to restart my PC.
EDIT AGAIN: I've also tried using the "/c remote.call("creative-mode", "disable", true)" command and that didn't work either. I've basically tried everything, and nothing has worked.

I haven't seen this issue before. Can you give me your save and list of mods so I can investigate on it? Also which Factorio version you are using.
It will also help if you can provide more details on how you put it in Creative Mode (e.g. what you did before), and the error when your game crashes if there is any.